Fibre material for nonwoven products

Abstract

The invention relates to a fibre material for nonwoven products, particularly bonded-fibre fabrics, or for composite fibre materials, in particular in the form of panel parts or moulded parts, or for paper-like planar materials, wherein the fibre material has fibres of a limited length, in particular short fibres, continuous fibres (filaments) and / or staple fibres, wherein the fibre material is based on fibre mixtures and / or mixed fibres based on natural polymers, which fibre mixtures and / or mixed fibres have chitin and optionally cellulose.

Description

[0001] FIBER MATERIAL FOR NONWOVEN PRODUCTS

[0002] Description

[0003] The present invention relates to a natural polymer-based fiber material with excellent biodegradability for use in nonwoven products, in particular nonwovens, or in fiber composite materials, in particular in the form of panels or molded parts, or in paper-like sheet materials. The invention further relates to nonwoven products, in particular nonwovens and products formed from nonwovens, fiber composite materials, in particular in the form of panels or molded parts, and paper-like sheet materials.

[0004] Nonwoven products are textile fabrics whose surface is formed not by weaving or knitting, but by interlocking the fibers of the fiber material and then securing them. Due to their versatile applications and comparatively low production costs compared to knitted and woven fabrics, nonwoven products continue to enjoy high annual growth rates.

[0005] The advantage of these nonwoven products, especially nonwoven materials, lies in their high moisture absorption. The manufacturing processes allow for high variability in density and thickness, which leads to extensive areal isotropy. These advantageous properties result in numerous possible uses, for example in medicine for hygiene products such as surgical drapes, bed sheets, wound dressings, gauze, etc.; in the household as all kinds of wipes and as decorative nonwovens, e.g. in the form of tablecloths, napkins, etc.; in the clothing industry as interlining nonwovens; and also for technical applications, e.g., insulating mats, cover mats, filter materials, or fiber composites, particularly in the form of panels or molded parts.In this respect, the present invention relates to a fiber material for the production of wipes, cleaning cloths, sanitary products, medical products and household cloths, these products being characterized by advantageous properties, in particular with regard to their behavior towards externally acting moisture, and with regard to their excellent biodegradability.

[0006] Flat products containing or made from the fiber material according to the invention can come in various forms. One example is so-called nonwoven products.

[0007] Nonwoven products are now considered a separate product group. Nonwoven products include nonwovens and nonwoven fabrics, and finished products made from them, often for cleaning and hygiene purposes. These often textile-like composite materials are flexible, porous sheet materials that are not formed by the traditional methods of weaving warp and weft or stitch formation, but rather by interlacing and / or cohesive and / or adhesive bonding of typical synthetic fibers, which can be in the form of continuous or finite-length prefabricated threads, as in-situ produced synthetic fibers, or in the form of staple fibers.

[0008] However, the fiber material according to the invention, which is specified in more detail below, is not limited to such nonwovens. Rather, the fiber material according to the invention is also suitable for the production of panels or molded parts or for the production of paper-like sheet materials.

[0009] Fiber composite materials, as they are available today as panels or molded parts, consist to a significant extent of synthetic raw materials. Typically, a synthetic, thermoplastic support fiber is used as a binder. Only by using binders and adhesives made from renewable raw materials can the advantages of the nonwoven material (made from natural fibers) and the products made from it be fully preserved, especially their biodegradability.

[0010] Accordingly, the invention particularly also relates to a fiber material for materials whose application areas include, for example, partition wall systems and molded parts (e.g., for packaging). Given that legislation as well as increased customer interest in many countries are placing increasing pressure on material manufacturers and end products to consider environmental impacts throughout the product life cycle, the present invention is based on the object of specifying a fiber material for use in nonwoven products, and in particular, composite materials. The fiber material is based on renewable raw materials and can thus be considered an environmentally friendly, cost-effective alternative to glass fibers and synthetic plastics.

[0011] The drastic price increase for petroleum and the fossil-based plastics produced from it is creating additional momentum. In many developments, the fiber of a nonwoven product, panel, or molded part is replaced with a renewable fiber, while the binding agent used to manufacture the nonwoven product or fiber composite continues to be made of synthetic, fossil-based plastics, negating the advantages of the environmentally friendly and renewable fiber.

[0012] The invention is based on the object of providing a fiber material based on natural polymers with excellent biodegradability for the production of nonwoven products or fiber composite materials or paper-like sheet materials, wherein the fiber material is suitable for a wide range of applications.

[0013] In particular, the fiber material should fall outside the scope of the EU's Single-Use Plastics Directive (SUPD), but also allow for further options to optimally adapt the properties of the nonwoven product, sheet, molded part, or paper-like sheet material to the respective requirements. These properties include, among others, accelerated biodegradation and, preferably, adjustable (increased) surface hydrophilicity.

[0014] This object is achieved according to the invention by the subject matter of independent claim 1, wherein advantageous developments of the invention are specified in the corresponding dependent claims. Accordingly, the invention relates in particular to fiber material for use as a filter and / or filling material for mouthpieces for tobacco applications, in particular for HNB product applications, wherein the fiber material is based on tow and / or staple fibers, in particular in the form of mixed fibers and / or fiber blends based on natural polymers, which comprise chitin and optionally cellulose.

[0015] The term "mixed fiber" used herein refers to a fiber made of different polymers, while the term "fiber mixture" or "mixture of fibers" refers to several fibers of different composition. Coated fibers are a special case of mixed fibers.

[0016] According to embodiments of the fiber material according to the invention, the fiber material is based on fibers of limited length, in particular mixed fibers of limited length, which consist of 5% to 100%, preferably 10% to 95%, more preferably 15% to 85%, more preferably 20% to 75%, more preferably 25% to 70%, more preferably 30% to 65%, more preferably 35% to 60%, more preferably 40% to 60%, and more preferably 45% to 55% chitin. In particular, the fibers of the fiber material have a length of 0.5 mm to 500 mm, preferably a length of 2 mm to 300 mm, and more preferably a length of 5 to 250 mm.

[0017] After cellulose, chitin is the most widely distributed biopolymer in nature. It is found in the exoskeletons of shellfish, as well as in insect shells and fungal cell walls. Chitin differs from cellulose by the presence of an N-acetyl group in its molecular framework. This significantly improves chitin's physical properties, particularly its durability and strength, compared to cellulose. Chitin also possesses exceptionally good adsorption properties. These properties are significantly enhanced and synergistically enhanced, particularly when combined with cellulose as a unified natural fiber complex.

[0018] With regard to the fiber material according to the invention, the following features are particularly to be emphasized: • Excellent biodegradability: The biodegradation is preferably 60 wt% or more, more preferably 70 wt% or more and even more preferably 90 wt% or more within 30 days in water and soil;

[0019] • not part of the SUPD (single-use plastics directive): chitin and cellulose fibres and also their mixed fibres or fibre blends are considered natural polymers and are therefore exempt from the directive;

[0020] • Temperature range: Application range up to 120° in gaseous media; and

[0021] • Specific filtration properties: Surface, fiber shape, fibrillation of the fibers can be influenced by process technology and tailored to the application.

[0022] Numerous potential applications for chitin are currently being discussed. In particular, chitin is already being used commercially for wound healing products and medical implants. However, it has been surprisingly discovered that the use of chitin as a fiber material for nonwoven products, especially nonwovens, or for fiber composites, especially in the form of panels or molded parts, or for paper-like sheet materials, also offers surprising advantages, particularly with regard to biocompatibility, biodegradability, and strength.

[0023] Biodegradability tests in water showed increased biodegradability of chitin and chitin / cellulose blended fibers and / or fiber mixtures compared to other regenerated cellulose fibers, as well as cellulose acetate. Excellent biodegradation was also observed in other media, such as soil or seawater. In all media, the fibers degraded within the prescribed time, with the fastest degradation occurring in water and soil. Here, the fibers degraded by over 80% within 15 days.

[0024] Various processes can be used to produce fibers from chitin.

[0025] For example, it is conceivable that chitin could be converted into chitin xanthate using a caustic base and carbon disulfide. The chitin xanthate is a viscous dispersion, which is then transferred by extrusion into a coagulation bath containing, for example, sulfuric acid and ammonium sulfate. The chitin regenerates in the coagulation bath and acquires a gel-like consistency. Filaments or fibers can be produced by drying this gel-like substance. In this context, reference is made, for example, to US Pat. No. 2,217,823 B.

[0026] Furthermore, it is conceivable to combine chitin and cellulose using caustic bases and carbon disulfide.

[0027] Finally, it is conceivable to form high-strength chitin fibers in a four-step process (cf. US Pat. No. 4,029,727 B). Chitin can be dissolved in a mixture of dichloroacetic acid and an anhydrous organic solvent. The chitin is then coagulated using an excess of organic liquid, which does not dissolve chitin. The coagulated material is then neutralized with a base bath. The chitin is then cold-drawn to produce an oriented chitin fiber.

[0028] Particularly preferably, the tow material according to the invention uses a mixed fiber and / or a fiber mixture which comprises chitin and cellulose.

[0029] In this context, it is conceivable that a solvent based on ionic liquids is used to produce the cellulose-chitin mixed fibers of the fiber material in order to combine cellulose and chitin.

[0030] Ionic liquids are salts that are liquid even at temperatures below 100°C and can dissolve many polymers, especially the long-chain polysaccharides of chitin. The solvent used in ionic liquids must be selected so that it is equally suitable for processing both cellulose and chitin. This makes it possible to process the raw materials chitin and cellulose into a single fiber in a single process step.

[0031] The cellulose-chitin mixed fibers produced in this way exhibit faster biodegradation compared to pure regenerated cellulose fibers and cellulose acetate. In the cellulose-chitin mixed fiber, chitin in particular has the structure-forming property. According to preferred embodiments of the fiber material according to the invention, this is based on chopped mixed fibers and / or fiber blends consisting of 5% to 100%, preferably 10% to 95%, more preferably 15% to 85%, more preferably 20% to 75%, more preferably 25% to 70%, more preferably 30% to 65%, more preferably 35% to 60%, more preferably 40% to 60%, and more preferably 45% to 55% chitin.

[0032] In particular, the fiber material according to the invention consists of 5% to 100%, preferably 5% to 70%, and more preferably 10% to 50% chitin.

[0033] The fiber material or the staple fibers of the fiber material are particularly suitable for the production of nonwovens and paper.

[0034] Although chitosan-based products are currently available on the market, it should be noted that chitin and chitosan differ in their property profiles. The use of chitin can lead to improved or new products being established on the market. Furthermore, the use of chitin as a raw material is more cost-effective because the derivatization of chitosan is eliminated.

[0035] The fiber material according to the invention provides a decisive step towards sustainable technology development by enabling the production of natural fiber nonwovens and natural fiber molded parts bonded to natural materials.

[0036] The fiber material preferably consists of 100% renewable raw materials.

[0037] The product according to the invention, which is formed from the fiber material according to independent claim 1, preferably comprises a binder. Particularly suitable binders are starch-based binders and dextrins, as well as biodegradable plastics such as polylactic acid (PLA) and polyhydroxybutyric acid (PHB). The binders can be introduced into the nonwoven laying process in powder, fiber, and flake form, mostly dry, but sometimes also exposed to steam to enable binder breakdown. The following binders are particularly suitable as binders:

[0038] - native starch (various types, dry and dissolved);

[0039] - pregelatinised starch (various types, dry and dissolved);

[0040] - modified starch;

[0041] - Dextrin;

[0042] - pulp;

[0043] - PLA; and / or

[0044] - PHB.

[0045] Polylactide (PLA) is a plastic made from renewable raw materials. It is processed in the same way as conventional mass-produced plastics. The melting point of PLA is below the decomposition temperature of natural fibers, allowing the production of biodegradable fiber composites.

[0046] Polylactide is a polyester based on lactic acid, which is produced by various bacterial species. The raw materials used are starch- or sugar-containing plants and organic waste.

[0047] Due to its properties, PLA falls somewhere between polyethylene terephthalate (PET) and polypropylene (PP). It is a polymer with a very wide range of applications. Furthermore, PLA's high molecular weight inhibits bacterial and fungal growth, making it well-suited for food packaging.

[0048] Polylactide degrades under high humidity and high temperatures. Such conditions are found, for example, in composting plants or biogas plants. Degradation occurs in two steps: first, the high-molecular-weight PLA is hydrolyzed to low-molecular-weight PLA. The fragments are then decomposed by bacteria. However, under typical usage conditions, PLA remains stable and retains its physical properties and molecular weight.

[0049] The fiber material according to the invention can comprise crimped fibers, preferably with 2 to 50 crimp arcs / cm, in particular with 10 to 20 crimp arcs / cm. This allows the fiber density in the nonwoven product to be adjusted. Alternatively or additionally, it is possible to adjust a specific surface area of ​​the fibers by selecting an appropriate cross-sectional shape for the fibers. In addition to a circular fiber cross-section, it is conceivable for the fibers of the fiber material to have a circular, trilobal, hexagonal, polygonal, star-shaped, quadrangular, X-shaped, K-shaped, C-shaped, or Y-shaped, and / or irregularly shaped cross-sectional geometry.

[0050] According to embodiments of the fiber material according to the invention, the fibers of the fiber material have a diameter between 500 nm and 500 pm, and preferably a diameter between 100 nm and 500 pm. In particular, the fibers of the fiber material have a particularly average tenacity on the smooth thread of 5 to 25 N / 5 cm.

[0051] The invention further relates to a nonwoven product which comprises the fibre material of the type according to the invention described above.

[0052] The nonwoven product may further comprise, in particular, fibrous binders, in particular PLA fibers and / or PHB fibers, wherein the weight fraction of the fibers of the fiber material in the nonwoven product is preferably greater than 70%.

[0053] The nonwoven product is in particular a mechanically formed nonwoven product, an aerodynamically formed nonwoven product, a hydrodynamically formed nonwoven product or an electrostatically formed nonwoven product.

[0054] To impart the desired strength properties to the nonwoven product, biopolymers are preferably used as binders. PLA and / or PHB in powder and / or fiber form, as well as starch, are particularly suitable. These binders can replace the conventional thermoplastic support fibers of fossil origin, which are generally used as state-of-the-art today.

[0055] In particular for the production of sheet or molded parts, the nonwoven product can be consolidated by converting a fiber web into a nonwoven fabric in which a bond between the fibers is consolidated, the bond between the fibers being produced by frictional engagement or by a combination of frictional and positive engagement by means of a mechanical consolidation process.

[0056] In this context, it is conceivable that the nonwoven product is consolidated, namely by converting a fiber web into a nonwoven fabric, in which a bond between the fibers is consolidated, whereby the bond between the fibers is produced by means of a chemical bonding process through material bonding by means of additives.

[0057] The additives may comprise a liquid binder, in particular native starch dissolved preferably in water, pregelatinized starch dissolved preferably in water, modified starch, dextrin dissolved preferably in water, pulp, PLA, and / or PHB. Alternatively or additionally, the additives may comprise fibrous binders, in particular binders made from renewable raw materials, in particular PLA fibers. Alternatively or additionally, the additives may comprise powdered binders, in particular pulp, chemically modified starch, pregelatinized starch, and / or PHB (polyhydroxybutyric acid).

[0058] In particular, the proportion of binder in the nonwoven product should vary between 10% and 30%.

[0059] According to embodiments, the nonwoven product has a basis weight of 15 to 500 g / m 2Particularly in this context, it is conceivable that the nonwoven product is one of the following products:

[0060] • a nonwoven fabric for hygiene products, in particular baby diapers or adult incontinence products,

[0061] • a nonwoven product for personal care products, in particular skin care wipes, preferably wet wipes, or hair removal strips,

[0062] • a nonwoven product for medical devices, in particular surgical drapes, disposable protective gowns, protective caps, mouth and nose protection, dressings, plasters or base material for tissue engineering,

[0063] • a nonwoven product for cleaning products in the household and commercial sector, in particular reusable cleaning cloths for floor cleaning, • a base nonwoven fabric for synthetic leather cloths, microfiber cloths, scouring media, vacuum cleaner bags,

[0064] • a nonwoven product for home furnishing, in particular covering or filling nonwovens for upholstered furniture, floor coverings and backing material for tufted carpets, nonwoven wallpaper, blinds and roller blinds, backing material for veneer,

[0065] • a nonwoven product for clothing, in particular interlining nonwoven fabric for shaping and stiffening in various clothing items, chemical and dust protection suits, thermal insulation nonwoven fabric in clothing, backing material for artificial leather for shoe manufacture, stiffening material for shoe caps, or

[0066] • a nonwoven material for technical applications, in particular drainage layer in civil engineering, roofing membrane support material in building construction, roof underlay, nonwoven fabric for thermal insulation and impact sound insulation, painter's fleece, filter fleece roll.

[0067] After the nonwoven product has been consolidated, it can be further compacted to produce a nonwoven product with a basis weight of 3,000 to 4,000 g / m2 The nonwoven product can be a fiber composite material, particularly in the form of a panel or molded part.

[0068] Using the nonwoven laying process, and particularly using PLA fibers, the best results in terms of strength and low specific gravity can be achieved for nonwoven products. The advantage is that nonwoven products with both low and high bulk densities can be produced, making them suitable as starting materials for both molded packaging parts and partition wall elements.

[0069] In particular, fibers of the fiber material according to the invention and starch-based binders processed in a mixing process result in very light and dimensionally stable boards after their compression.

[0070] Suitable binders include starch-based binders and dextrins, as well as biodegradable plastics such as polylactic acid (PLA) and polyhydroxybutyric acid (PHB). The binders can be introduced into the nonwoven laying process in powder, fiber, and flake form, primarily in dry form, but sometimes also with steam to facilitate binder decomposition.

[0071] Various bonding models are possible for the fiber-matrix system. The first bonding model is the linear bond (fiber bond). This model corresponds to the currently most commonly used process. The fiber used, made of chitin and optionally cellulose, has a higher melting point in the core than in the sheath. The binder fiber is only melted externally in the furnace and remains solid on the inside. This melting fiber bonds with the surrounding nonwoven fibers, is then cooled and hardens. The binder fiber thus not only connects the fibers of the nonwoven to one another, but also absorbs mechanical stress itself, as its fiber structure remains intact.

[0072] Another possible bonding model is the point-bonding (powder). A point-bonding occurs when the binding agent is introduced into the fleece in powder form. Activated by heat and / or steam, it forms nodes in the fiber tangle, thus creating a dimensionally stable, cross-linked mat.

[0073] Of course, liquid adhesives / binders are also suitable. Liquid binders based on native starch, pregelatinized starch, modified starch, dextrin, pulp, PLA, and / or PHB are suitable for this purpose.

[0074] According to one conceivable implementation of the invention, a nonwoven fabric with randomly arranged fibers is produced, particularly using the aerodynamic principle. The fiber web is then compacted in a thermobonding oven, and the adhesive used is activated by exposure to heat and, depending on the type, with the addition of steam. Hot melt adhesives such as PLA and PHB can be used. Glues such as starches and dextrin are also suitable.

Claims

Patent claims 1. Fibre material for nonwoven products, in particular nonwovens, or for fibre composite materials, in particular in the form of panels or moulded parts, or for paper-like sheet materials, wherein the fibre material comprises fibres of limited length, in particular short fibres, continuous fibres (filaments) and / or staple fibres, wherein the fibre material is based on natural polymer-based mixed fibres and / or fibre mixtures which comprise chitin and optionally cellulose.

2. Fiber material according to claim 1, wherein the fibers of limited length, in particular short fibers, the continuous fibers and / or the staple fibers on which the fiber material is based, consist of or comprise 5% to 100%, preferably 10% to 95%, more preferably 15% to 85%, more preferably 20% to 75%, more preferably 25% to 70%, more preferably 30% to 65%, more preferably 35% to 60%, more preferably 40% to 60%, and more preferably 45% to 55% chitin.

3. Fiber material according to claim 1 or 2, wherein the mixed fibers of the fiber material are cellulose-chitin mixed fibers and / or wherein the fiber mixture of the fiber material is a cellulose-chitin fiber mixture, and wherein, for producing the cellulose-chitin mixed fibers and / or for producing the cellulose-chitin fiber mixture of the fiber material, cellulose and chitin are preferably bonded together by using a solvent based on ionic liquids.

4. Fiber material according to one of claims 1 to 3, wherein the fiber material contains cellulose-chitin mixed fibers and / or a fiber mixture of chitin fibers and cellulose and / or cellulose acetate fibers.

5. Fiber material according to one of claims 1 to 4, wherein the fiber material has crimped fibers preferably with 2 to 50 crimp arcs / cm, in particular with 10 to 20 crimp arcs / cm.

6. Fiber material according to one of claims 1 to 5, wherein the fibers of the fiber material have a circular, trilobal, hexagonal, polygonal, star-shaped, quadrangular, X-, K-, C-, or Y-shaped and / or irregularly shaped cross-sectional geometry.

7. Fiber material according to one of claims 1 to 6, wherein the mixed fibers contain cellulose and / or wherein the fiber mixture contains fibers made of cellulose.

8. Fiber material according to one of claims 1 to 7, wherein the mixed fibers contain cellulose acetate fibers and / or natural fibers and / or wherein the fiber mixture contains fibers made of cellulose acetate.

9. Fiber material according to one of claims 1 to 8, wherein the fibers of the fiber material are arranged at mutual distances in an unregulated arrangement, and wherein the fibers are mutually entangled and / or hooked.

10. Fiber material according to one of claims 1 to 9, wherein the fibers of the fiber material have a length of 0.5 mm to 500 mm and preferably a length of 2 mm to 300 mm and more preferably a length of 5 to 250 mm.

11. Fiber material according to one of claims 1 to 10, wherein the fibers of the fiber material have a diameter between 500 nm to 500 pm and preferably a diameter between 100 nm to 500 pm.

12. Fiber material according to one of claims 1 to 11, wherein the fibers of the fiber material have a particularly medium fineness on the smooth thread of 5 to 25 N / 5 cm.

13. A nonwoven product comprising the fiber material according to any one of claims 1 to 12.

14. Nonwoven product according to claim 13, wherein the nonwoven product further comprises in particular fibrous binders, in particular PLA fibers and / or PHB fibers, wherein the weight fraction of the fibers of the fiber material in the nonwoven product is greater than 70%.

15. The nonwoven product according to claim 13 or 14, wherein the nonwoven product is a mechanically formed nonwoven product, an aerodynamically formed nonwoven product, a hydrodynamically formed nonwoven product, or an electrostatically formed nonwoven product.

16. A nonwoven product according to claim 15, wherein the nonwoven product is consolidated by converting a nonwoven fabric into a nonwoven material in which a bond between the fibers is consolidated, wherein the bond between the fibers is produced by frictional engagement or by a combination of frictional and positive engagement by means of a mechanical bonding process.

17. A nonwoven product according to claim 15, wherein the nonwoven product is consolidated by converting a nonwoven fiber web into a nonwoven fabric in which a bond between the fibers is consolidated, wherein the bond of the fibers is produced by means of a chemical bonding process by means of additives.

18. Nonwoven product according to claim 17, wherein the additives comprise a liquid binder, in particular native starch dissolved in preferably water, pregelatinized starch dissolved in preferably water, modified starch, dextrin dissolved in preferably water, pulp, PLA, and / or PHB.

19. Nonwoven product according to claim 17 or 18, wherein the additives comprise fibrous binders, in particular binders made from renewable raw materials, in particular PLA fibers.

20. Nonwoven product according to one of claims 17 to 19, wherein the additives comprise powdered binders, in particular pulp, chemically modified starch, pregelatinized starch and / or PHB (polyhydroxybutyric acid).

21. A nonwoven product according to any one of claims 18 to 20, wherein the proportion of binder in the nonwoven product varies between 10% and 30%.

22. A nonwoven product according to any one of claims 16 to 21, wherein after the consolidation of the nonwoven product, the nonwoven product was further compacted.

23. Nonwoven product according to one of claims 13 to 22, wherein the nonwoven product has a basis weight of 15 to 500 g / m 2 has.

24. Nonwoven product according to one of claims 13 to 23 and in particular according to claim 23, wherein the nonwoven product: • a nonwoven fabric for hygiene products, in particular baby diapers or adult incontinence products, • a nonwoven product for personal care products, in particular skin care wipes, preferably wet wipes, or hair removal strips, • a nonwoven product for cleaning products in the household and commercial sector, in particular reusable cleaning cloths for floor cleaning, • a base nonwoven fabric for synthetic leather cloths, microfiber cloths, scouring media, vacuum cleaner bags, • a nonwoven product for home furnishing, in particular covering or filling nonwovens for upholstered furniture, floor coverings and backing material for tufted carpets, nonwoven wallpaper, blinds and roller blinds, backing material for veneer, or • a nonwoven material for technical applications, in particular drainage layer in civil engineering, roofing membrane carrier material in building construction, roof underlay, nonwoven fabric for thermal insulation and impact sound insulation, painter's fleece, filter fleece roll.

25. Nonwoven product according to one of claims 13 to 22, wherein the nonwoven product has a basis weight of 3,000 to 4,000 g / m 2 has.

26. Nonwoven product according to claim 25, wherein the nonwoven product is a fiber composite material, in particular in the form of a plate or molded part.